The existing X-ray human body back-scattering scanning and inspecting apparatus normally uses a single-point scanning method, which uses a relatively large-scale back-scattering detector. The technique uses a longitudinal scanning manner where X-ray machine and detector move up and down in synchronization, or a scanning manner where the X-ray machine rotates coaxially (or translates) while the detector moves laterally. Only one beam of light irradiates on a surface of the human body at a time whatever manner is used. Therefore, it is concerned in the technical field how to accelerate the scanning without degrading image quality and enhancing the irradiation dose on the human body.